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The world's best gem articles, published weekly.

Most Recent Articles

Standard Gem Sizes Chart

Will your gem fit in a standard setting? Use this chart of standard gem sizes for popular cuts and also learn how to estimate gem weight based on size.…

A Guide to Early Victorian Romantic Period Jewelry

The Romantic Period marked the start of the Victorian Era. Learn about the typical qualities of Romantic Period jewelry, including its sentimental…

Jewelry Torches: A Beginner’s Guide

Jewelry torches are essential for jewelry making. Learn about different fuel sources and types of torches and how to choose the right one for you.…

Prosopite Value, Price, and Jewelry Information

Prosopite is usually a nondescript mineral with no gem significance. However, beautiful blue specimens are sometimes cut for jewelry.

Buying Gem Parcels and Quality Rough

To make money, novice faceters have to buy gem parcels as well as hand-picked quality rough. Learn how a combination of both approaches can lead…

A Guide to Antique Georgian Jewelry

Authentic Georgian jewelry is rare. Before you buy, learn about the notable pieces and qualities of this antique style, including its intricate…

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Gem Price Guide

The world's best online resource for gemstone appraisal

Over 15 years, we have assembled detailed pricing and value information for appraising over 70 different gemstones. The values in our guide come from a variety of sources including primary and secondary gemstone dealers, jewelers, miners, and wholesale suppliers of commonly traded gemstones.

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Gemstone Encyclopedia

Our Gemstone Encyclopedia has information on over 300 gemstones, from traditional and popular jewelry standards to collector’s stones that rarely appear for sale. Each entry has photos and detailed information about the gem’s properties. Entries for jewelry stones also have price guidelines and discussions of their most important value factors.

Emerald

Emerald has been synonymous with the color green since ancient times. A fine emerald is a truly breathtaking sight, and this member of the beryl family deserves its placement among the traditional “Big Four” gems along with diamond, ruby, and sapphire.

Onyx

For millennia, artisans have carved intricate cameos from black-and-white onyx. Solid black onyxes, faceted or cabbed, are also popular jewelry stones.

Sapphire

Few gems have held our attention over millennia as well as sapphire. The pure blue colors and excellent durability of this gem-quality member of the corundum family make for an exceptional gemstone. However, not all sapphires are blue. The September birthstone comes in every color of the rainbow (except red).

Moissanite

When it comes to engagement ring stones, there’s a lot to consider. In the moissanite vs diamond debate, we’ll look at three main factors: beauty, durability, and price.

Hematite

Hematite has a long history of use as a pigment. As a gemstone, this material is often carved but very rarely faceted. Despite its association with blood and the color red, hematite’s color can range from black and metallic gray to brownish red in thin slivers or crystals.